Zoning Off Of A Combi.

[SimonG]

Up at a big country hall. 4 floors currently run off a big Worcester combi and big Warmflow combi. They run three bathrooms each.
Yes they shouldn't be there but previously occupied by a couple who apparently got what they asked for.
Fast forward to the new occupants who do a lot of entertaining and people staying over.
All 6 bathrooms redone and all radiators on 3 floors changed to cast iron radiators.
Warm flow runs all the ground floor radiators and three bathrooms. It's about 4 years old and current occupants hate it.
Worcester runs floors 1, 2, attic and 3 bathrooms.
Worcester in the kitchen and just can't heat all the radiators.

Now about 10 foot from the boiler in the ceiling void there is space and access to the rising pipework.

So my plan is to cut an access into this void and split the pipework. Allowing the current pump to do the 1st floor and then stick an 8 m pump in to feed 2nd floor and attic, complete with two ports.

Question is, do you think the 8 m pump will rob the first floor when the two zones are on together?

I was thinking of using the combi boiler, re rated to highest output, pump to feed upto the void and then use two pumps in there.

 

[ShaunCorbs]

Should be fine just make sure your primaries are bigger you could cct the boiler so you don’t interfere with it’s pump or llh it

 

[SimonG]

Can't change anything from the boiler to void. Will give cct a try.

 

[king of pipes]

Low loss header would be the way but limited for space the risk is there. Kop